Not Applicable.
Not Applicable.
This invention relates to a shiftable compound planetary transmission. More particularly, this invention relates to a two-speed compound planetary transmission that provides for shifting while under load and includes a set of drive gears that are in constant mesh with cluster gears that rotate around the drive gears during operation.
It is well known that various types of motors and transmissions are used in auger drive systems to change the rate at which augers bore holes into the ground. Auger systems are mounted on the end of a boom and above the drill bit. Two-speed drives are desirable for earth boring applications. Low speeds and high torque is used for boring through the ground and high speeds and low torque is used to spin-off or clean the drill bit after digging is complete.
One type of auger drive system changes operational speeds by the use of a two-speed motor and a one-speed transmission. In this configuration, the speed of the motor is selectively adjusted between two speeds to adjust the operational speed of the augers, while gear ratio in the transmission remains constant. This type of transmission system is more than twice the weight and larger than a one-speed motor. The weight and size of the two-speed motor makes it more difficult for an operator to control the end of the boom when positioning the drill bit over a desired location. Not only is it difficult to control the end of the boom, some auger machines simply cannot support the weight and size of a two-speed system.
Another type of auger drive system shifts speeds through the use of a one-speed motor and a two-speed transmission. In this construction, the speed of the motor remains constant and the gears in the transmission are shifted between two gear sets to change the operational speed of the auger. In some prior art devices, the gear sets are not in constant mesh, therefore the gears must be stopped and manually shifted to change gear sets. If the gears are not stopped prior to shifting, the gear teeth will grind against each other causing the gear teeth to wear down and/or break. Various types of lock-out prevention hydraulic circuitry is used on these types of devices to prevent inadvertent shifting while the gears are still in motion. This transmission system is inefficient due to the continual stopping and starting of the auger that is necessary to change gears.
There are other types of systems that utilize one-speed motor and multiple-speed transmissions that have gears that are in constant mesh. For example, U.S. Pat. No. 4,777,837 to Lehle includes a plurality of gear sets that are mounted on two fixed parallel shafts that are in constant mesh with gears mounted on a drive shaft. Although the gears are in constant mesh, the system requires synchromesh couplings in conjunction with a clutch mechanism to change gear sets. This system is inefficient in that a two-step process is required to change gear sets in addition to the parallel shafts that are fixedly mounted to the housing which reduces the power output potential.
In addition, U.S. Pat. No. 5,489,013 to Buuck et al. discloses a system that includes a plurality of gears sets that are in constant mesh. This system allows for some planetary motion, but does not utilize compound epicyclic gearing. Further, a set of various sized clutch packs are included, but again, this device does not utilize compound epicyclic gearing. This multi-piece construction is complex and difficult to assemble.
Accordingly, there remains a need for a power-shiftable transmission, such as an auger drive which overcomes the above drawbacks and deficiencies. More specifically, there remains a need for a transmission for an auger that is of a simple construction and easy to install on an auger. In addition, there remains a need for a transmission that allows for a simplified construction for shifting between gears while under loading. Further, there remains a need for a transmission that allows for gears to rotate around a primary drive shaft to increase the power output potential. There is also a need for a transmission that has a reduced weight and size so that the auger machine can support such a system on the end of a boom. The objective of this invention is to solve or substantially reduce the problems normally associated with known prior art transmission systems for auger drives and other devices.
Accordingly, in one of its aspects, the present invention provides a power transmission device for shifting the operating speed of a machine.
In another of its aspects, the present invention provides a device for shifting the operating speed of a machine while under load.
In still another of its aspects, the present invention provides a method for shifting the operating speed of a machine through the use of a transmission device.
According to the present invention, the foregoing and other objects are achieved by a power transmission device for shifting the operating speed of a machine while under load. The machine generally includes a casing, an input and an output shaft. The device includes a clutch mechanism, a primary carrier, a cluster gear, a ring gear, a first gear and a second gear. the clutch mechanism is operably associated with the input shaft. The primary carrier is located within the casing and operably coupled to rotate the output shaft. The cluster gear is rotatably coupled to the primary carrier. The ring gear is coupled to the casing and is in mesh with the cluster gear. The first gear is rotatably mounted within the casing and is in mesh with the cluster gear. The second gear is rotatably mounted on the first gear and is in mesh with the cluster gear. The cluster gear is adapted to rotate around the first and second gears when one of the first gear and the second gear is engaged thereby rotating the output shaft at the operating speed corresponding to the engaged gear.
The invention further provides a device for shifting the operating speed of a machine while under load. The machine generally includes a casing, an input and an output shaft. The device includes a cluster gear, a first gear, a second gear, an engaging means and a means for allowing the cluster gear to rotate around the first and second gear. The cluster gear is rotatably coupled to the casing and associated with the output shaft. The first gear is rotatably mounted within the casing and is in mesh with the cluster gear. The second gear is rotatably mounted on the first gear and is in mesh with the cluster gear. The engaging means is operably associated with the input shaft and adapted to selectively engage either the first or second gear. The present invention includes means that allows for the cluster gear to rotate around the first and second gears. One of the first gear and the second gear is engaged thereby rotating the output shaft at the operating speed corresponding to the engaged gear.
The present invention further provides a method for shifting the operating speed of a machine through the use of a transmission device. The machine includes a casing, an input shaft and an output shaft. The device includes a primary carrier, a cluster gear, a ring gear, a first gear and a second gear. The primary carrier is located within the casing and operably coupled to rotate the output shaft. The cluster gear is rotatably coupled to the primary carrier. The ring gear is coupled to the casing and is in mesh with the cluster gear. The first gear is rotatably mounted within the casing and is in mesh with the cluster gear. The second gear is rotatably mounted on the first gear and is in mesh with the cluster gear. The clutch mechanism is adapted to selectively engage one of the first gear and the second gear, and wherein the cluster gear is adapted to rotate around the first and second gears when one of the first gear and the second gear is engaged thereby rotating the output shaft at the operating speed corresponding to the engaged gear. The method comprises rotating the input shaft, engaging the clutch with one of the first gear and second gear, rotating the cluster gear around the first and second gears and rotating the output shaft at the operating speed corresponding to the engaged gear.
Additional objects of invention, together with the advantages and novel features appurtenant thereto, will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned from the practice of the invention. The objects and advantages of the invention may be realized and attained by means and instrumentalities and combinations particularly pointed out in the appended claims.